science fiction, but scientists are hard at work  trying to unlock the secrets of human hibernation.  

And if they succeed, it could be  a game changer for everything from  

curing diseases to deep space travel. Hibernation is just scientifically weird.  

It’s more than bears crawling  in a cave and hitting snooze. 

When animals go into hibernation, they  exhibit symptoms similar to those of  

diabetes and Alzheimer's. Bears, for example,  become resistant to insulin, and their brains  

tiptoe the line of neurodegeneration. But when  they wake up, they’re “cured.” If scientists can  

figure out what's so special about hibernators,  they may be able to use this knowledge  

to treat diseases that afflict us humans. So, what would it take for humans to actually  

hibernate? To answer this, we first need to know  why some animals hibernate in the first place.  

For warm-blooded animals, it can take a lot of  energy to maintain a constant body temperature.  

That can be a really big challenge when  their source of energy, food, is scarce.  

Hibernation is a survival mechanism that conserves  energy by lowering the body’s core temperature,  

slowing the heart rate, and shifting into  a lower metabolic state, known as torpor. 

For example, when arctic ground  squirrels enter hibernation  

their temperature plummets from 37°C to -3°C  and their metabolic rate drops by about 99%. 

Humans, by comparison, are stuck with a relatively  fixed body temperature of 37°C. Aside from minute  

variations, like when we sleep, our temperature  only changes as a way to signal danger. Like  

when we’re sick, we get a fever. Just a  few degrees off either way can mean death. 

But this isn’t a hard and fast rule. In 1999, a  woman fell while skiing, crashing head first into  

a frozen stream. When medics arrived 80 minutes  later, her body temperature had dropped to 13.7°C,  

rendering her clinically dead. But she  miraculously survived! The extreme cold lowered  

her metabolism so her brain wasn’t oxygen-starved. Lack of oxygen can lead to permanent brain damage  

in a matter of minutes… usually not enough  time to make it to the operating table.  

An ongoing trial led by researchers at  the University of Maryland is testing this  

idea of suspended animation — otherwise called  emergency preservation and resuscitation, or EPR.  

The idea is that it can help patients whose  hearts have stopped due to excessive blood loss. 

By replacing their blood with ice-cold  saline, it lowers their body temperature  

to 10°C.

This decreases the body’s need for oxygen,  buying the operating team more time. 

After surgery is complete, the body is warmed up  and the heart is restarted. The trial is expected  

to wrap in December of 2022, and they’ve already  used the technique on a handful of patients. 

And NASA is working to take suspended animation  to the next level. In 2014, the agency  

funded research on extended human hibernation  and found that it would cut down on the amount  

of food, water, and supplies needed, making deep  space travel more practical. Because in theory,  

if we lowered your temperature enough, eventually  your metabolism would come to a standstill. 

According to Spaceworks, the company contracted  by NASA to do the study, astronauts could safely  

be kept in a hibernation-like state for 14 days  with current medical capabilities. A four-person  

crew could work in shifts with three in  cryogenic pods, while one runs the ship. 

Expanded human trials are  expected in 2024.

So, we may not be able to slow a person’s  metabolism for so long that they can actually  

hibernate…yet. But given time, we all  might be hibernating sometime soon. 

Another thing scientists are looking at for  deep space travel is artificial gravity.  

If you want to learn more, watch Julian’s  video here. If you had the option to hibernate,  

would you? Let us know down in the comments.  Make sure to subscribe and thanks for watching.